Conventionally, a flat panel detector (hereinafter simply called “FPD”) is used as a detector for detecting light or radiation. The FPD includes a semiconductor layer, an application electrode, an active matrix substrate, a driver and a processor. The semiconductor layer converts light or radiation information into charge information. The application electrode is formed on a surface of the semiconductor layer to apply a high voltage power supply to the semiconductor layer. The active matrix substrate has a plurality of switching elements to read the charge information from the semiconductor layer. The driver drives this active matrix substrate for reading. The processor amplifies and digitizes the charge information read from the active matrix substrate. A power supply apparatus is connected to the FPD, and various power supplies are provided from the power supply apparatus.
Reference is made to FIG. 5. FIG. 5 is a view showing an outline construction of a power supply apparatus in a conventional example. The power supply apparatus 61 outputs two or more types of driving power supplies V1 provided for the driver, a plurality of processing power supplies V2 provided for the processor, and a high voltage power supply V3 provided for the application electrode. This power supply apparatus 61 includes a power output unit 63 formed of a plurality of output circuits 64 arranged on lines of the various power supplies V1, V2 and V3, respectively, to output the various power supplies V1, V2 and V3 individually. The power output unit 63 is controlled by a controller 65.
An operating unit 71 is connected to the power supply apparatus 61. The operating unit 71 is formed of a computer having an input device such as a keyboard. When the user operates this operating unit 71, the operating unit 71 receives instructions to an FPD 75, and gives the received instructions to the controller 65. A utility power source 79 is connected to these power supply apparatus 61 and operating unit 71 through an uninterruptible power supply system (hereinafter simply called “UPS”) 77.
In the conventional example constructed in this way, the power supply apparatus 61 and operating unit 71 are operable with electric power supplied from the utility power source 79, and the UPS 77 accumulates electric power. When the user inputs startup instructions to the operating unit 71, the controller 65 outputs the various power supplies V1, V2 and V3 in a predetermined order. Consequently, the power supplies are successively provided for the driver and the like of the FPD 75. When stop instructions are inputted to the operating unit 71, the controller 65 stops the output of the various power supplies in a predetermined order. Consequently, the power supplies for the driver and the like of the FPD 75 stop. The predetermined orders are decided for the purpose of protection of each circuit such as the driver of the FPD 75.
When an instantaneous interruption or power failure occurs and the voltage of the utility power source 79 falls, the UPS 77 supplies electric power to the power supply apparatus 61 and operating unit 71. Consequently, the various power supplies are continuously provided for the FPD 75 from the power supply apparatus 61. The operating unit 71 also continues its operation to be able to receive instructions from the user. Therefore, when the user inputs stop instructions to the operating unit 71, the FPD 75 can be stopped normally. Thus, even when the utility power source 79 undergoes a voltage drop, the power supplies are not stopped in an order other than the predetermined order, such as the output of the various power supplies to the FPD 75 stopping all at once. Therefore, the FPD 75 can be protected from damage, destruction or breakdown (see Patent Document 1. for example).
[Patent Document 1]
Japanese Unexamined Patent Publication No. 2003-258218